Luminescent cyclometallated iridium(III) complexes having acetylide ligands

Abstract

The present invention relates to phosphorescent (triplet-emitting) organometallic materials. The phosphorescent materials of the present invention comprise Ir(III)cyclometallated alkynyl complexes for use as triplet light-emitting materials. The Ir(III)cyclometallated alkynyl complexes comprise at least one cyclometallating ligand and at least one alkynyl ligand bonded to the iridium. Also provided is an organic light emitting device comprising an anode, a cathode and an emissive layer between the anode and the cathode, wherein the emissive layer comprises a Ir(III)cyclometallated alkynyl complex as a triplet emitting material.

The invention claimed is: 
     
       1. A compound having the formula I: 
       
         
           
           
               
               
           
         
       
       wherein: X 11^ X 2  is a substituted or unsubstituted bidentate cyclometallated aromatic ligand; X 1  and X 2  are independently selected from C and N; Z is an acetylide ligand having the structure: —C≡C—R 1 , —C≡C—(C≡C) x —R 1 , or —C≡C-(A-C≡C) y —R 1 , each R 1  is independently selected from the group consisting of H, alkyl, cycloalkyl, alkenyl, cycloalkenyl, aryl, heteroaryl, Si(R 2 ) 3 , M(L) z , and a heterocyclic group, each of which may be substituted or unsubstituted; each x is independently selected from 0-5; each y is independently selected from 0-5; each R 2  is independently selected from H, alkyl, cycloalkyl, alkenyl, cycloalkenyl, aryl, heteroaryl, and a heterocyclic group; M is a metal atom; L is a mono-, bi- or tridentate ligand; z is 0-5; A is aryl or heteroaryl; Y is a monodentate ancillary ligand; b is 0, 1, 2, or 3; the sum of a+b+n is 4 or 5; and Cat is an optional cation the charge of which provides a net neutral charge for formula I, wherein n is 2 and a is 2. 
     
     
       2. A compound having the formula I: 
       
         
           
           
               
               
           
         
       
       wherein: X 1^ X 2  is a substituted or unsubstituted bidentate cyclometallated aromatic ligand; X 1  and X 2  are independently selected from C and N; Z is an acetylide ligand having the structure: —C≡C—R 1 , —C≡C—(C≡C) x —R 1 , or —C≡C-(A-C≡C) y —R 1 , each R 1  is independently selected from the group consisting of H, alkyl, cycloalkyl, alkenyl, cycloalkenyl, aryl, heteroaryl, Si(R 2 ) 3 , M(L) z , and a heterocyclic group, each of which may be substituted or unsubstituted; each x is independently selected from 0-5; each y is independently selected from 0-5; each R 2  is independently selected from H, alkyl, cycloalkyl, alkenyl, cycloalkenyl, aryl, heteroaryl, and a heterocyclic group; M is a metal atom; L is a mono-, bi- or tridentate ligand; z is 0-5; A is aryl or heteroaryl; a is 1; b is 1; n is 2; the sum of a+b+n is 4; and Cat is an optional cation the charge of which provides a net neutral charge for formula I, wherein Y has the formula —C≡N—R 3 ; and R 3  is selected from the group consisting of alkyl, cycloalkyl, alkenyl, aryl, aralkyl, and heteroaryl. 
     
     
       3. A compound having the formula III: 
       
         
           
           
               
               
           
         
       
       wherein C^N is a substituted or unsubstituted cyclometallated ligand; R 1a  and R 1b  are independently selected from the group consisting of H, alkyl, cycloalkyl, alkenyl, cycloalkenyl, aryl, heteroaryl, Si(R 2 ) 3 , M(L) z , and a heterocyclic group, each of which may be substituted or unsubstituted; each R 2  is independently selected from H, alkyl, cycloalkyl, alkenyl, cycloalkenyl, aryl, heteroaryl, and a heterocyclic group; M is a metal atom; L is a mono-, bi- or tridentate ligand; z is 0-5; and Cat is an optional cation the charge of which provides a net neutral charge for formula III.